1. Field of the Invention
The present invention relates to a stringed musical instrument such as an acoustic guitar, a mandolin, a violin, etc., and more particularly to an acoustic enhancement device which enhances the amplification, sustain, and reverberation of the sounds generated by plucking, striking or otherwise vibrating the instrument strings.
2. Description of Related Art
It is well known that the resonance of a stringed musical instrument sound box can be enhanced by incorporating within or above the sound box, a plurality of springs, coils or strings which can respond to the vibrations of the primary strings. These sound box springs amplify and sustain the resonant effect of the sounds generated by plucking, striking or otherwise vibrating the instrument strings. Those acoustic enhancement devices which are attached to the outside of the instrument can alter the balance of the instrument, interfere with a performer's playing, and be visually distracting. Therefore, it is preferable if the acoustic enhancement device is disposed within the soundbox of the instrument.
Those existing acoustic enhancement devices which are interiorly disposed are generally designed according to one of two arrangements. In one arrangement, the springs are stretched across the entire interior of the sound box longitudinally from the neck end to the shoulder strap attachment end, substantially parallel to the instrument strings. Due to their length, the springs are able to pick up a substantial portion of the vibrations present within the soundbox. Also, due to being stretched across the longitudinal centerline of the soundbox, the resonating springs more effectively re-emit sound out of the soundbox through the sound hole.
In the second arrangement, one end of the springs is connected to the inside top surface of the sound box, directly under the bridge, and the other end of the springs is connected to the neck end of the soundbox. The springs in this latter arrangement do not pick up the vibrations from the interior of the soundbox as well as in the former arrangement because the springs of the latter arrangement are shorter and span a smaller portion of the soundbox. However, by being connected to the soundbox directly under the bridge, the springs more effectively pick up vibrations from the bridge. The springs in this arrangement are also stretched across the longitudinal centerline of the soundbox, so they too effectively re-emit sound out of the soundbox through the sound hole.
The related art is represented by the following patents of interest.
U.S. Pat. No. 231,084, issued on Aug. 10, 1880 to Thomas Peaker, describes a violin with two or more adjustable strings or iron bars inside the body stretched from one end of the body to the other. Peaker does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
U.S. Pat. No. 685,920, issued on Nov. 5, 1901 to August Heck, describes a stringed musical instrument with an adjustable resonator inside the body stretched from one end of the body to the other. Heck does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
U.S. Pat. No. 1,588,730, issued on Jun. 15, 1926 to Isidor Hessel, describes a resonator device for violins. Hessel does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
U.S. Pat. No. 3,623,390, issued on Nov. 30, 1971 to Jack R. Pitt, Jr., describes an adaptor for stringed musical instruments comprising a plurality of parallel vibrating members rotatably mounted to a base at one end and disposed transverse to the strings of a stringed musical instrument so that a head at the other end of each of the vibrating members is positioned to engage a string of the stringed instrument. Pitts, Jr. does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
U.S. Pat. No. 4,762,046, issued on Aug. 9, 1988 to Roberto Aspri et al., describes a sound reverberator device for detachable connection to the strings of a string musical instrument. Aspri et al. '046 does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
U.S. Pat. No. 4,984,493, issued on Jan. 15, 1991 to Helmut F. K. Schaller, describes a mechanism for applying an adjustable counter-tension to the spring anchor of a tremolo device used with a guitar or similar stringed musical instrument. Schaller does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
U.S. Pat. No. 5,567,895, issued on Oct. 22, 1996 to Roberto Aspri et al., describes a sound reverberator of a string musical instrument comprising one or more pre-tensioned metal springs secured internally of the sound box. Aspri et al. '895 does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
U.S. Pat. No. 5,567,896, issued on Oct. 22, 1996 to Peter Gottschall, describes a string musical instrument having an intermediate plate mounted in the interior of the sound box at a predetermined inclination to provide sound amplification. Gottschall does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
U.S. Pat. No. 5,581,043, issued on Dec. 3, 1996 to Richard D. Bowar, describes a stringed musical instrument with adjustable baffles within the sound box that enable the user to change or adjust the wavelength of the music produced by the instrument to more closely coincide with the overtone transmission capability of the ambient environment. Bowar does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
German Patent document 351,046, published on Mar. 30, 1922, describes a tone enhancer device for a stringed musical instrument. German '046 does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
German Patent document 2,818,168, published on Nov. 8, 1979, describes an undesirable resonance damper for stringed musical instruments. German '168 does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
Great Britain Patent document 256,157, published on Aug. 5, 1926, describes a resonator device for violins. Great Britain '157 does not suggest an acoustic stringed instrument enhancement device according to the claimed invention.
These devices all suffer from multiple deficiencies. Foremost, the existing devices are designed to be permanently built into the instrument at the time of the instrument's construction. Hence, most acoustic enhancement devices cannot be attached to previously constructed, standard store-bought guitars. Those devices that can be later attached, require that the soundbox be disassemble and reglued, or that additional holes be drilled into the soundbox, in order to incorporate the acoustic enhancement device thereinto. Thus, even if later retrofitting is theoretically feasible, such an acoustic enhancement device would not be desirable because the standard musician does not have the proper tools nor skill to properly disassemble and reassemble his or her instrument. Further, even if skill, tools and cost are not considerations, a musician would be reticent to make such major structural alterations because of the risk that it could detrimentally alter the instrument's acoustics.
Another deficiency with existing acoustic enhancement devices is that most can not be selectively engaged or disengaged, as desired by the musician. U.S. Pat. No. 5,567,895 issued to Aspri et al. does disclose a pre-tensioned interior spring which can be engaged or disengaged selectively. However, to accomplish this selective-engagement function, the Aspri et al. '895 invention incorporates a complex mechanism for into the guitar design which requires extra holes be drilled into the soundbox. The device is not intended for use by attachment to a standard store-bought guitar. Therefore, a need exists for an unobtrusive, adjustment-free, stringed instrument acoustic enhancement device which can be removably placed within the soundbox of a standard, conventional stringed instrument without causing damage thereto.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.